Clear entire wave area when plane wave frequency changes, see #309

phetsims · Jan 11, 2019 · 3b4141e · 3b4141e
1 parent 1cd86d1
commit 3b4141e
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Showing 2 changed files with 20 additions and 3 deletions.
diff --git a/js/common/model/Lattice.js b/js/common/model/Lattice.js
@@ -234,8 +234,9 @@ define( require => {
     clearRight( column ) {
       for ( let i = column; i < this.width; i++ ) {
         for ( let j = 0; j < this.height; j++ ) {
-          this.setCurrentValue( i, j, 0 );
-          this.setLastValue( i, j, 0 );
+          for ( let k = 0; k < this.matrices.length; k++ ) {
+            this.matrices[ k ].set( i, j, 0 );
+          }
           this.visitedMatrix.set( i, j, 0 );
           this.allowedMask.set( i, j, 1 ); // Initialize to 1 to support plane waves, which is never masked.
         }

diff --git a/js/common/model/Scene.js b/js/common/model/Scene.js
@@ -291,6 +291,10 @@ define( require => {
       // @private
       this.stepIndex = 0;
 
+      // @private - when the plane wave frequency is changed, don't update the wave area for a few frames so there is no
+      // flicker, see https://github.com/phetsims/wave-interference/issues/309
+      this.stepsToSkipForPlaneWaveSources = 0;
+
       // When the user changes disturbance type, the button pops out and waves stop
       this.disturbanceTypeProperty.link( () => {
         this.button1PressedProperty.value = false;
@@ -322,7 +326,11 @@ define( require => {
 
         // When changing the plane wave frequency, clear the wave area to the right of the wave
         if ( this.waveSpatialType === Scene.WaveSpatialType.PLANE ) {
-          this.lattice.clearRight( this.barrierLatticeCoordinateProperty.value );
+          this.clear();
+
+          // when the plane wave frequency is changed, don't update the wave area for a few frames so there is no
+          // flicker, see https://github.com/phetsims/wave-interference/issues/309
+          this.stepsToSkipForPlaneWaveSources = 2;
         }
         else {
           this.handlePhaseChanged();
@@ -460,6 +468,13 @@ define( require => {
      * @private
      */
     setPlaneSourceValues( amplitude, time ) {
+
+      // When the plane wave frequency is changed, don't update the wave area for a few frames so there is no flicker,
+      // see https://github.com/phetsims/wave-interference/issues/309
+      if ( this.stepsToSkipForPlaneWaveSources > 0 ) {
+        this.stepsToSkipForPlaneWaveSources--;
+        return;
+      }
       const lattice = this.lattice;
 
       const barrierLatticeX = this.barrierTypeProperty.value === Scene.BarrierType.NO_BARRIER ?
@@ -745,6 +760,7 @@ define( require => {
       this.continuousWave2OscillatingProperty.reset();
       this.isAboutToFireProperty.reset();
       this.barrierTypeProperty && this.barrierTypeProperty.reset();
+      this.stepsToSkipForPlaneWaveSources = 0;
     }
 
     /**